When blood is lost, the chief immediate need is to cease further blood loss followed by replacing the lost blood volume. This critical need is important for allowing the remaining red blood cells to oxygenate body tissue albeit at a reduced capacity. When the body detects the lower hemoglobin levels, from extreme blood loss, compensatory mechanisms begin. There are currently no resuscitative fluids that provide oxygen to hypoxic cells and tissues following major blood loss.
Oxygen therapeutics have traditionally been categorized as either hemoglobin-based oxygen carriers (HBOCs) or perfluorocarbons (PFCs). Unlike blood, HBOCs and PFCs do not require blood typing, have a long shelf life, do not transmit blood borne diseases, and in most cases do not need refrigeration. Despite these promising attributes the wide-spread utility of HBOCs and PFCs has been limited by concerns regarding hypertension from systemic arteriolar constriction and leukocyte activation, respectively.